Fluid containers



April 5, 1969 R. w. YOUNG 3,438,550

FLUID CONTAINERS Filed March 1, 1965 p7 INVENTOR 6 BY M FIG. 4 ML ATTORNE YS United States Patent 0 3,438,550 FLUID CONTAINERS Richard W. Young,Wellesley Hills, Mass., assignor t0 Polaroid Corporation, Cambridge,Mass., a corporation of Delaware Filed Mar. 1, 1965, Ser. No. 435,950

Int. Cl. B65d 35/08, 35/14, 35/16 U.S. Cl. 222-107 8 Claims Thisinvention relates to fluid containers and, more particularly, to fluidcontainers adapted to retain a photographic processing composition.

In the photographic processes identified hereinafter, frequently it isrequired that a small quantity of liquid material be applied in arelatively thin layer over a fairly large surface area. Specifically,for example, a photosensitive film may be processed by the applicationto a surface thereof of a layer of a liquid containing photographicprocessing reagents, for example, a silver halide developing compositionof the type disclosed in U.S. Patent No. 2,543,181. In general,photographic fluid processing compositions possess a relatively limitedshelf-life due to, in part, the degradation effects of environmehfilconditions upon the active components of the processing compositions.For example, the presence of environmental oxygen in contact with aliquid photographic processing composition generally provides for theoxidative degradation of various active components of the compositionsuch as, for example, the photographic silver halide developing agentsretained within such formulations, which may be further catalyzed bycontact between the liquid and the container retaining same, where suchretaining means are not inert with respect to the liquid. In an effortto provide fluid containers particularly adapted to retain a relativelysmall quantity of liquid material for the aboveidentified purpose,several patents have been issued directly relating to the constructionof such fluid containers. U.S. Patents Nos. 2,543,181, 2,634,886,2,653,- 732, 2,674,532, 2,702,146, 2,723,051, 2,750,075, 2,903,- 829,3,056,491, and 3,056,492 disclose fluid containers particularly adaptedto retain photographic processing compositions which are formed of aplurality of layers including, respectively, an outer layer, forexample, kraft paper; a layer of metallic foil, for example, lead foil;and an inner lining, or layer, of a thermoplastic resin, for example, apolyvinyl acetal such as polyvinyl butyral, polyvinyl chloride, and thelike.

Employment of the containers set forth in the prior art to retain afluid photographic processing composition, over an extended period oftime, results in some deterioration of the respective processingcomposition due to contact with environmental vapor, irrespective of thefact that such containers are substantially impervious to vapor. Theaccess of fluid photographic processing composition to vapor contact,derived from the external environment, even to a limited extent,provides progressive deterioration of the relative stability of theprocessing composition. In addition, the presence of minute defects inthe polymeric inner liner such as, for example, pinholes and the like,arising during fabrication of the container, further adversely affectthe stability of the retained fluid compositions, by providing contactof the liquid with the potentially active metallic foil stratum of thecontainer.

The present invention, however, comprehends an inexpensive, preferablydisposable, inert container particularly adapted to provide forretention of a liquid such as a photographic processing composition,which is in a quantity suflicient to carry out a single application tothe respective surface of the sheet, or sheets, to be treated, whereinthe retained liquid is effectively insulated from contact withexternally derived vapor whereby to enhance the storage stability ofsuch liquid, and wherein the fluid contents of the container aremaintained in condition for direct application of said surfaces in anefficient and economical manner, especially, when such container isdirectly-aflixed to, or in apposition to, a surface to be treated.

The objects of the present invention are therefore to provide improvedfluid containers, that is, inert fluid containers which effectivelyinsulate and retain a liquid medium from contact with externally derivedvapor.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the product possessing the features,properties and the relation of components which are exemplified in thefollowing detailed disclosure, and the scope of the application of whichwill be indicated in the claims.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawings wherein:

FIGURE 1 is a perspective view of one form of fluid container prior tointroduction of a liquid thereinto and subsequent closure of thecontainer walls;

FIG. 2 is a cross-sectional view comprising the fluid container ofFIGURE 1 after introduction of a fluid photographic processingcomposition and closure of said containers Walls;

FIG. 3 is a fragmentary plan View of the continuous material which isused in the formation of the container blanks of FIGURE 1; and

FIG. 4 is a cross-sectional view of the continuous material of FIG. 3.

In one embodiment, the container will be an elongated structure, havinga length of at least twice its width, and is relatively flat, having adepth which is only a fraction of its width. The container also will bedeformable in its filled and sealed condition so that it can be curvedin the direction of its width, for example, about a radius equal to itswidth, without danger of rupturing its seal. A sealed passage willextend the length of the container along one edge thereof and will bethe weakest of the edge seals which define the liquid containing cavityand which confine the contents of said cavity.

- The present invention is specifically concerned with improved fluidcontainers, of the last-mentioned type, which include, in general, arelatively thin, flexible layer of glass having a continuous polymericlayer superposed on one surface, preferably a laminate structurecomprising a relatively thin, flexible layer of glass having acontinuous polymeric layer contiguous each surface, and, mostpreferably, a laminate which includes an outer layer comprising acontinuous polymeric layer, a layer of glass, and a polymeric innerlining, or layer, inert with respect to the photographic processingcomposition to be retained therein, for example, inert to theconventional, highly caustic, organic nitrogen-containing photographicprocessing compositions commercially employed in the photographicindustry.

In addition, the present invention is concerned with providing frangiblecontainers, of the last-mentioned type, possessing at least one flexibleand deformable wall, which exhibits differential strength of thecontainers respective edge seals, thus facilitating substantiallyuniform rupture and distribution of the containers retained fluidcontents, by means of a predetermined passage orifice, upon theapplication of stress to the containers deformable surfaces.

The container is most preferably formed from a single, essentiallyrectangular blank folded medially, as illustrated in FIGURE 1. Thecontainer is constructed of a multilayer material comprising walls 1 and2, said individual walls being formed by medial fold 3. A surfaceportion of one of said walls as, for example, portion 4 of wall 2, issuitable for receiving and in part confining said liquid, and asubstantially equal surface portion of the other of said walls as, forexample, surface portion 5 of wall 1 is suitable for further confiningsaid fluid upon closure of said walls. The container may also be formedfrom two essentially rectangular blanks secured together at marginaledges. It is so simply constructed that the container blank of FIG. 3,from which the container is formed, may be cut without waste from acontinuous strip of laminated sheet material, permitting the material ofthe container walls to be processed and the container to be filled,sealed and served as part of one continuous operation.

The aforesaid fluid container is preferably constructed, as illustratedin FIG. 2, of an outer polymeric layer 6 as a backing layer, said outerlayer 6 being preferably formed of a thin, deformable, tough polymericmaterial, generally in the order of 0.5 mil in thickness as, forexample, a polyester such as polyethylene terephthalate and the like. Athin film, or sheet, 7 comprising glass approximately 0.5 mil inthickness, and having its dimensions predetermined according to theintended use, has layer 6 suitably adhered thereto and/or coated thereonas, for example, by means of a conventional adhesive composition such asDu Pont Adhesive No. 46,950 (trade designation of E. I. du Pont deNemours and Co., Wilmington, Del., for a commercially distributedpolyester resin adhesive) where layer 6 comprises a polyester. A layer 8comprising a thermoplastic material, inert to the fluid composition tobe retained within the container, for example, fluid photographicprocessing composition 9, such as polymerized vinyl chloride, forexample, 90% vinyl chloride and 10% vinyl acetate, approximating 1.5mils in thickness, the aforementioned polyester, approximating 0.5 milin thickness, preferably overcoated with, or having adhered by means ofthe last-identified adhesive, polymerized vinyl chloride, polymerizedvinyl butyral, and the like, approximating 1.5 mils in thickness, issuitably adhered to and/ or coated on the opposite surface of layer 7.

Where desired, however, the illustrated container may comprise glasslayer 7 and inner liner, or layer 8, as the sole essential layersforming the container walls, whereupon glass layer 7 is in effect theouter layer of the walls.

The respective polymeric layers, coating or liners may be adhered to theglass layer by any of the coating and/or laminating procedures wellknown to the art. Where the polymeric layer, or layers, are pre-cast andthen laminated to the glass layer, it will be preferred to utilize anadhesive coating or layer, which adhesive layer is itself stable, orstabilized, against interaction with the containers fluid contents, andis selected based upon its adhesive capacity with respect to effecting auniform bond between the selected polymeric film and the glass. Theemployment of an intermediate adhesive layer also affords an additionallayer enhancing the stability of the container, and its retained liquid,by providing an added barrier coating for retaining the containersliquid contents. Alternatively, the polymeric layers may be directlycoated on the glass layer, for example, by hot melt extrusion ofthermoplastic polymer, for example, a thermoplastic vinyl polymer, suchas polymerized vinyl chloride or a thermoplastic olefinic polymer suchas polymerized ethylene or propylene, or the like, on the respectivesurface, or surfaces, of the glass layer.

In the completed, closed, liquid-carrying container, polymeric layer 8serves both to substantially prevent direct contact of the retainedfluid with vapor impervious glass layer 7 and as a means of bondingtogether the facing marginal portions of said container bordering theenclosed liquid when, for example, the marginal portions are subjectedto direct sealing by means of heat and/ or pressure and/or an adhesivecomposition and thus, upon bonding of said portions, provides means forsealing the liquid within the container.

The last-mentioned adhesive composition, illustrated by numeral 10, maybe overlaid on a marginal portion 11 of polymeric layer 8 which, whenbonded to a facing marginal polymeric portion 12, may serve as a meansfor bonding the facing marginal portions differentially with respect toother facing marginal portions 13, 14, 15 and 16.

Upon closure of walls 1 and 2, marginal surface portions 11, 13 and 15come into contact with marginal surface portions 12, 14 and 16,respectively, and may be suitably bonded together, as previously noted,and, when thus bonded, provide, in conjunction with fold 3, means foreffecting a completely sealed enclosure, or space.

Referring to FIG. 3, there is shown a blank 17 from which a preferredembodiment of the present inventions novel container may be formed, saidblank 17, as shown, being substantially rectangular in shape and havinga length equal to the container length and a width approximately twicethe width of the finished, filled container. As previously stated, blank17 is preferably formed of a composite, deformable sheet materialdescribed above and comprising the plurality of strata illustrated inFIG. 4.

Outer polymeric layer 6, present in the preferred embodimentillustrated, as the aforementioned backing or support layer, hascontiguous thereto layer 7 which, as detailed, is a thin film, or sheet,of vapor-impervious glass. Contiguous the opposite surface of said glasslayer 7, is layer 8 of thermoplastic material inert to, for example,fluid photographic processing composition. Layers 6 and 8 are relativelythin, generally being in the order of 0.5 mil in thickness, and, as apractical matter, in the preferred embodiment need only be sufficientlythick to be characterized as continuous.

Along one edge of blank 17, there may be provided a strip 10 of asuitable thermoplastic composition which exhibits, preferably, a lesseradhesive affinity for polymeric layer 8 than the latter has for itself,for example, upon direct sealing and/ or by means of the adhesiveemployed to affix marginal surface portions 13- to 14 and 15 to 16.

Container 19, illustrated in FIG. 2, is formed by folding blank 17 alonga substantially medial line 3 extending the length of the container andthen securing together the faces of marginal portions 13 to 14 and 15 to16 along the edges of the container and the facing marginal surfaceportions 11 to 12 along the long edge of the container. As previouslymentioned, the several marginal portions may be secured together by theapplication of heat and/ or pressure and, in addition, it may bepreferable to adhesively secure together a narrow strip 18 of thecontainer walls adjacent to the fold line 3. This latter provides a thinleading edge for the container over which a suitable pressure applyingdevice, such as a pressure roll, or doctor blade, may readily advance tocompress the container walls and to thereby effect the release of thecontainer contents by differential hydraulic rupture of the sealedmarginal surfaces, preferably along the long edge of the container. Asillustrated, the seal along the long edge of the container is preferablyeffected between inner polymeric layer 8 and the material of strip 10which, as hereinbefore indicated, may be a material which possesses alesser adhesive affinity for polymeric layer 8 than the polymeric layerdoes for itself as adhered in the remaining marginal portions. Thus thelatter bonds exhibit an adhesive capacity substantially stronger thanthe seal along the long edge.

This structure assures a unidirectional release of the containerscontents upon application of compressive force to the walls of thecontainer. In one preferred embodiment, to insure a uniform separationof the marginal portions along the long edge of the container, when thecontainer is subjected to a liquid releasing force, strip 10 not onlyextends to the very edge of the container but is also substantiallywider than the width of the seal between marginal portions 11 and 12 andadditionally extends within the liquid confining cavity of thecontainer, as

shown in FIG. 2. A further precaution against the hazard of an unevenseal consists in displacing the blank containing strip beyond the longedge of the blank to which it is adhered. As a result, strip 10 projectsbeyond both long edges of the bond.

Where inner polymeric layer 8 comprises the previouslyidentifiedpreferred polymer, polyvinyl chloride, coating 10 may comprise any oneof the following illustrative compositions:

1) cc. of a 10% solution of Saran F-120 (trade name of Dow ChemicalCompany, Midland, Mich., for a thermoplastic resin produced by thepolymerization of vinylidene chloride) in methyl ethyl ketone and 10 cc.of a 10% solution of nitrocellulose in methyl ethyl ketone;

(2) 100 cc. of a composition comprising: 10.0 g. of Acryloid B- (solid)[trade name of Rohm & Haas Company, Philadelphia, Pa., for an acrylicester resin], 3.4 g. of /2 second cellulose nitrate, and 86.5 cc. ofethyl acetate;

(3) cc. of a 10% solution of ethyl cellulose in methyl ethyl ketone and20 cc.'of a 10% solution of Acryloid B72; and

(4) cc. of a composition comprising: 5 g. of Bakelite NYGV and 5 g. ofBakelite NYGL (trade names of Bakelite Corporation, a division of UnionCarbide and Carbon Corporation, New York, N.Y., forpolyacrylonitrile-polyvinyl chloride resins), 100 cc. of acetone, 1 g.of Saran F and 3 g. of Acryloid B72 (solid).

Wherein inner liner 8 comprises a polyvinyl acetal such as polyvinylformal, polyvinyl acetal, polyvinyl butyral, and the like, preferablypolyvinyl butyral, thermoplastic adhesive coating 10 may comprise, forexample, ethyl cellulose, a mixture comprising ethyl cellulose andparaflin at a ratio of -1 1, and the like.

In the formation of the container, the contents may be introduced as thecontainers walls are being sealed together. For example, the long edgesof the container may be sealed together before the blank is severed fromthe stock of material from which it is formed. During the sealingtogether of the long edges, the desired quantity of liquid content .forthe container is introduced between the secured walls of the blank andthereafter the short edges are sealed together and the finishedcontainer severed from the remainder of the sheet stock. Under theseconditions, the sealing is preferably effected by the application ofheat and/ or pressure, and uniform heat and/or pressure may be employedto all marginal portions being sealed together in view of theditferential between the adhesive properties of strip 10 and those ofpolymeric layer 8. In

the alternative, differential heat and/or pressure and/or ture, orseparation, to obtain directional release of the retained fluidcomposition.

In one preferred form of the container for spreading a liquidphotographic processing composition to a thickness of approximately0.003 of an inch of an area approximately 3 inches by 4 inches, acontainer 3 inches long and having maximum thickness of A of an inch canbe used. The overall width of such container will be approximately of aninch and the width of the seals at the marginal areas will beapproximately A of an inch, while the seal at the release edge of thecontainer will be approximately of an inch. The overall thickness of thesheet materials from which the container walls are formed may beapproximately 0.0025 of an inch with each of layers 6, 7 and 8approximately 0.0005 of an inch thick and adhesive layers intermediatelayers 6 and 7 and intermediate layers 7 and 8 approximately 0.0005 ofan inch thick.

The relative maximum thickness of flexible, deformable glass layer 7 isonly restricted by the relative degree of end use flexibility requiredof the containers walls. Recognizing that the flexibility of the glasslayer will be directly related to the relative thickness of the layer,and the fact that flexibility, in general, increases with a decrease inthickness, the specific thickness employed, in a given instance, will beselected in accordance with the flexibility required by the end use. Inaddition to the fact that the glass layer provides a container withessentially zero degree of permeability to gaseous and liquid materials,the substantially chemically inert glass layer also possesses a lowcoeflicient of thermal expansion and conductivity, less weight andsuperior puncture resistance, when compared with the prior arts metallicfoil layers, as well as an essentially zero degree change of dimensionwith change in the relative humidity of the storage environment. Thusthere is provided a container, for the storage of sensitive photographicprocessing compositions, which possess essentially zero degree ofpermeability to atmospheric gases and zero degree of permeability withrespect to the escape of such liquids through the walls of thecontainer, by reason of a vapor barrier layer which is chemically inertto the retained processing composition and which exhibits a high degreeof flexibility as well as strength.

The aforesaid material and constructions provide a container capable ofsubstantially confining a liquid photographic processing compositionadapted for processing an exposed photosensitive film, said containerseffectively preventing loss of liquid content due to exudation,absorption, evaporation, and the like, and acting to preserve said fluidsubstantially free .from environmental contamination. It will beunderstood that the liquid may be introduced into the container in aninert atmosphere.

It will be further understood that both the form and capacity of thecontainer and the dimensions thereof are predetermined relative to theintended use of the subject container. It will be apparent thatalternative forms and arrangements thereof may be provided within thescope of the invention. Such modifications may, for example, comprise aliquid-carrying portion of the container having either a greater orlesser traverse or longitudinal dimension than the container shown, orthe modified container may have separable marginal surface portions forreleasing the retained fluid which vary from the straightline portionsillustrated above, or the container may be fabricated in accordance withthe parameters set forth in US. Patent No. 3,037,670.

Since certain changes may be made in the above product without departingfrom the scope of the invention herein involved, it is intended that allmatter contained in the above description or shown in the accompanyingdrawing shall be interpreted as illustrative and not in a limitingsense.

What is claimed is:

1. A rupturable, single use container having a pair of opposed wallssecured together to provide a liquid retaining cavity, at least one ofsaid walls being flexible and deformable, each of said walls comprisinga plurality of layers, at least one of said layers consistingessentially of a continuous glass film, the inner layer of each of saidwalls comprising a polymeric material inert to the liquid to be retainedwithin said cavity, and the bonded marginal portions of one edge of saidpair of opposed walls exhibiting substantially less adhesive capacitythan the remaining marginal portions of said pair of opposed walls.

2. A rupturable, single use fluid container as defined in claim 1,wherein said polymeric material comprises polyvinyl chloride.

3. A rupturable, single use fluid container as defined in claim 1,wherein said polymeric material comprises polyvinyl butyral.

4. A rupturable, single use fluid container as defined in claim 1,wherein said glass layer is positioned intermediate said inner layer andan outer layer comprising a polymeric material.

'5. A rupturable, single use fluid container as defined in claim 4,wherein said polymeric material comprising said outer layer comprisespolyethylene terephthalate.

6. A rupturable, single use fluid container as defined in claim 1,wherein a thermoplastic adhesive is positioned between the bondedmarginal portions of said edge exhibiting substantially less adhesivecapacity than said remaining marginal portions, said thermoplasticadhesive exhibiting substantially less adhesive aflinity for saidpolymeric material than said polymeric material exhibits for itself,said remaining marginal portions being adhered together by saidpolymeric material bonded to itself, whereby said containerpreferentially opens along said bonded marginal portions of said edgeexhibiting substantially less adhesive capacity, upon application ofpressure to said container.

7. A rupturable, single use fluid container as defined in claim 1,wherein said liquid containing cavity retains a photographic processingcomposition.

8. A rupturable, single use fluid container having a pair of opposedWalls secured together to provide a liquid retaining cavity, at leastone of said Walls being flexible and deformable, each of said Wallscomprising a plurality of essential layers, said plurality of layersincluding successively an outer layer comprising polyethyleneterephthalate, a layer comprising a continuous glass sheet, and an innerlayer comprising polyvinyl chloride, and the bonded marginal portions ofone edge of said pair of opposed walls exhibiting substantially lessadhesive capacity than the remaining marginal portions of said pair ofopposed Walls.

References Cited UNITED STATES PATENTS 2,366,514 1/1945 Gaylor 161-204 X2,457,785 12/1948 Slayter et el. 65-181 2,889,078 6/1959 Thomas 222 '107X 2,977,264 3/1961 Shapero et al. 2'22107 X 3,089,801 5/1963 Tierney etal. 156 1 X 3,152,515 10/1964 'Land 222 107 X ROBERT B. REEVES, PrimaryExaminer.

F R. I-DANDREN, Assistant Examiner.

US. Cl. X.R. 161194, 204-

